If your Mac Type1 fonts have rough or jagged edges when displayed on your
screen in Mac OS 9.2 and earlier, you will most likely need to install
Adobe Type Manager to help render the Type1 fonts with smooth edges on
your screen.
Adobe Type Manager is needed to help render Type1 fonts and also to print
Type1 fonts to a non postscript printer in Mac operating systems 9.2 and
earlier, OS X has built in support and does not need ATM but OS X Classic
mode will need ATM installed to view Type1 fonts on screen with out the
jagged edges.
You may get the free version of Adobe Type Manager Light for Mac at this location
http://www.adobe.com/products/atmlight/main.html